Super Bright with 5 Modes- The safety bike tail light use 14 pcs LED lamp beads. One-Touch Switch With with 5 lighting modes: Chase mode - Fast chase mode - Breathing lamp - Flash - Slow flash. wide 180-degree beam angle, improve the safety of night riding.USB Rechargeable Built-in Battery- Built-in 300mAh lithium polymer durable battery & long battery life to meet your daily needs. Comes with USB charging cable, a full charge takes about 1 hour only, can be charged by USB cable via computers, chargers or portable power banks.Waterproof & Safety- Made of aluminum alloy + PC material, IPX4 dust-proof and waterproof, do not afraid of the impact of bad weather such as rainy days on the tail lights. Strong brightness, a great accessory to ensure your safety when riding at night.Lightweight & Portable- The taillight only weights about 40g, compact design and sturdy built for more security and convenience. Flexible strap design for fitting most handlebar, easy to be fixed on any bicycle. This bike tail light is the best choice to improve your visibility and safety.Easy to Mounting- The rear bicycle light can be easily installed and released without any tools. This bike rear light can be attached to virtually any bike frame, fork, seat post, handlebars or helmet, it also can be hung onto your backpack, helmet, running gear,dog collars, or anywhere on your clothing.